I bought one at Sun's today for $3.99; I'd never cooked a live one before and somehow, I don't think I did it right.

I steamed it for 16 minutes (it was 2 lbs.). At the store, the butcher said 10 min, checker said 15. Then, I read 8 minutes a pound. BUT, it was definitely undercooked.

After water came to a boil, I put flame on med. low and put the crab in the steamer. (This is what my Chinese neighbor said to do -- others things on youtube said to do high flame, one said for 20 minutes. (My neighbor said she never cooks them, tho.)

What did I do wrong? AND, trying to eat some, the shell cut my thumb badly (crab's revenge?)

I have to agree that there is a bit of variation in what may work for you. Following some tips on this board, I also steamed 2lbs for 15-17 mins and got undercooked crab (fat and tomalley runny, still somewhat translucent meat inside). Flame was at 5 out of 7, so I think hard steam is needed. I steamed another 10 minutes to get it cooked. I enjoyed the difference in flavor and texture but I don't think I'd do this if I'm trying to feed others. Boiling definitely gets the job done faster for a crowd and still tastes great.

The legs cooks faster than the body. If you feel it's underdone, you can yank off the legs and put the rest back in for 3 to 5 mins. Some of my family members do this routinely, allowing 8 to 10 mins for the legs, then 3 mins for the rest, feeling that each section is then cooked optimally.

Lucky's has a three-day (Fri, Sat, Sun) sale on "local crab" is in its sale flyer for this week -- but no price given (presumably because the flyer went to print before they settled on the wholesale price). I notice in this thread that people aren't always making a distinction between cooked crab and live crab, so read carefully.

Piazza's San Mateo also said they were local. And that's what was printed on their flyer, so I hope they were correct. We certainly waited long enough, especially since this was the first day they had them. The crab was good enough, though the meat was not as tightly packed as I had hoped, and there was a fair amount of water in the crab.

I always take crab home whole, having once long ago made the mistake of agreeing to "cracked and cleaned" crab, not realizing they were going to powerhose all the tomalley and flavor out of the poor waterlogged critter.